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"NO WHiZZING" !!

I have been working on my 04 RT for the last three weekends doing a lot of maintenance that has been long overdue, plus a surprise replacement of the left side throttle body, which was not in the plans (butterfly valve was broke). Removed and cleaned out fuel tank, new fuel filter, replaced O2 sensor, adjusted valves, new battery, replaced fluids, new plugs, and the scary-hell of trying to get a stuck K&N oil filter off ! (it has a smooth body, no ridges to work with and the nut almost stripped)

Today, the engine was finally running smoothly enough to take a test ride around the block...However...when I was slowly riding down the street, the ABS light was still flashing, it never set itself or went off. I'd squeeze the brakes, and no power to them. Stopped and depressed both brakes, noticed I wasn't hearing that "whizzing" sound? Turned motor off, left electrical on, still no whizzy sound as I depressed on the brakes, which is what I "used to hear" on this RT.

My friend and I started going over the bike, suspecting maybe something electrical got either disconnected or "broke". Checked fuses, relays, wiring under the tank, etc. Never found anything obviously wrong? Few more test starts of the bike, but ABS just keeps flashing away, but system never kicked in.

I do not know the full details of how this system works, but the current "guess" is that something is not allowing the "whizzer" motor to function? Perhaps it has seized up or other issue I'm not aware of?

This bike has not been ridden for almost a year now. It got parked around the end of May of last year and hasn't been run since. Part of the problems I have noticed while working on the RT were moisture accumulation/build-up issues. I live about 100 miles NW of Houston and its humid most of the year around here. Had signs of water in the oil, about a quart in the fuel tank and in the transmission fluid when I drained it the last two weekends.

I am wondering if moisture got built-up in the ABS unit and either siezed up the "wizzer" unit or other issues?

At this point, I really do not know what direction to go to next with this new problem?

The whizzy booster is controlled by the Moronic computer; telling the computer to activate the ABS starts with the wiring from the brakes.
The front brake wires are:
Green with a black runner at the brake lever - this becomes white and blue after the first harness connector; this goes to pin 40 of the computer connector.
Gray - this becomes white with a yellow runner after the harness connector; this goes to pin 39 of the computer.
The rear brake wires are:
Yellow at the foot lever - this becomes yellow and green after the harness connector; this goes to pin 41 of the computer connector.
Green/Black - this becomes yellow/black after the harness connector; this goes to pin 7 of the computer.

The front & rear are on different lines, so if this happens (actually, "doesn't happen") with either brake Firmly depressed, then the computer becomes the first suspect. Carefully disconnect that big main connector and inspect the pins for straightness & alignment, water, and corrosion; some WD-40 and a careful nylon scrub pad may help here.

Does the brake light come on with either brake applied? That will tell you if the computer is receiving the control line input. This is a famous (or infamous) fake-you-out spot: if you have a bad bulb or socket, the computer will change the voltage to - and thus your observation of - the brake light. Make sure both bulbs are actually good and operating "properly".

Possibly relay #7 or fuse #5 (Motronic control circuits) are bad.

I don't know if the ABS pumps can be electrically tested independently, but if this applies to both front & rear, that points back to the computer or a harness/connector issue.

Some Direction Finally

Thanks for the input...hopefully I will find out I have "no" input to the computer and it will be an easy fix. There was some concern about the rear brake light while fiddle-faddling through all of it. The micro switch on the rear brake was physically removed while I had that right side plate off. Then mounted back on and I can hear the micro-switch "clicking" with the brake pedal actuated. Will do some other tests with your suggestions.

It will be this weekend before I get back on that project. This is the irritating part, I now work in Houston, but the RT is up in Bryan, Texas, about 100 miles away. I don't have a work space, so its up at a friends house in Bryan for now. Only gives me a few hours on Saturdays & Sundays to work on it. Hopefully I can resolve this issue without further fanfare of surprises.

Just something else to consider is the strength of the battery. If the battery voltage is low the ABS lights will flash.

This project including putting in a new battery two weekends ago and its been kept on a Battery-Tender while parked. Have checked it with a voltmeter also, that thought crossed my mind as well. Will chase down the wiring, bulbs this Saturday when I get back. Then again, may just parked this another week and rebuild some carbs on the other upcoming project...no whizzy unit on that bike !

Have one bike left running at the moment....will start off with a breakfast ride Saturday Morning - get my priorities straight

"will start off with a breakfast ride Saturday Morning - get my priorities straight "
Well you definitely have your priorities straight! Still lots of pretty bluebonnets in your area, I rode through BCS last Tuesday. You mention that the bike had been parked for a year and there were signs of moisture accumulation. Have you cleaned all of the possible wiring connections? It's an onerous task, but one that is necessary on occasion. I'll be interested in hearing what you find. Just acquired a 2004 R1150GSA with whizzy brakes and it's a new system to me.

It's WHIZZING Now !!

Did my breakfast ride through Sam Houston Forest to some off-beat cafe in the direction of Huntsville, Tx.
Then started on the 5th weekend of the RT rejuvenation project, lack of a better term?

After reading the posting about lights, switches, etc. Started with pulling the tail-light assembly. Checked bulb, it was staying on, but I wasn't fully sure if this was tail-light with brake filament or other? System is one bulb for tail light and one bulb for brake, single filaments. Ok, so why is it on? Checked foot brake assembly first, I had taken the microswitch off when I removed the lower side panel. It seemed to be switching ok. So now the dreaded right handlebar brake assembly. That took some doing trying to find all the screws and remember the locations. One was stripped, so it will need to be replaced, and it was on the very bottom, nasty spot to get to. So this assembly has had some past work by previous owner I assume?

Finally got to micro-switch, and started to diddle with it. The little button part the metal band touches wasn't popping in/out correctly. Then I hit it with a small screw-driver, still nothing, then I happened to touch brake also. System started "whizzing" finally and the brake-bulb finally went out. Pulled microswitch off and sprayed with some blue-shower stuff I had, and some small needle-nose pliers and it finally started popping in/out.

Did more testing, and basically I learned that the microswitch is not exclusive to turning the brake light on/off. If the switch is not depressed, but the handle is depressed, then the EVO unit will still activate the brake light. But if I'm holding the brake handle in at other times, but the switch is not depressed, then nothing happens. The micro switch is somehow a sort of redundant part of a sequence for the EVO system, but not exclusive either, very confusing.

Anyway, got to point that everything seemed to work ok, and carefully reassembled the right handle brake assembly. I am not looking forward to replacing the brake fluid, which is next time around on this project. I do have the funnel now !

This was the last bastion of this project was getting the EVO system to work properly again. Finally started reassembling the bike, and when I tried to put the "tupperware" back on, snapped yet another piece on the right side bottom near the exhaust. Arrrgg...I just finished "bondo-ing" another section next to that I snapped off because I didn't see/forgot about those two screws when I first started diss-assembly and snapped that initially.

The right side panel for the RT would not fully line up on the screw-holes. My guess is that three to four weeks of leaning up against a wall, the panel warped a bit? It did get to 80 plus degrees down here the last couple of weeks. Finally put panel on, minus two of the screws for now. Will work on it next time I have to pull them off, probably when I do the brake fluid eventually.

This will be my last "panel-bike" ! GS or R bike is starting to look a whole lot better now !